Thanks Jeff

Interesting concept, can you give me any examples of their usage, what kinds of data etc.?

Thanks

 ===============================================================================
Stuart Forrest PhD
Library Systems Specialist
Beaufort County Library
843 255 6450
[log in to unmask]

http://www.beaufortcountylibrary.org

For Leisure, For Learning, For Life




-----Original Message-----
From: Code for Libraries [mailto:[log in to unmask]] On Behalf Of Mixter,Jeff
Sent: Friday, December 19, 2014 10:20 AM
To: [log in to unmask]
Subject: Re: [CODE4LIB] rdf triplestores

A triplestore is basically a database backend for RDF triples. The major benefit is that it allows for SPARQL querying. You could imagine a triplestore as being the same thing as a relational database that can be queried with SQL.

The drawback that I have run into is that unless you have unlimited hardware, triplestores can run into scaling problems (when you are looking at hundreds of millions or billions of triples). This is a problem when you want to search for data. For searching I use a hybrid Elasticsearch (i.e. Lucene) index for the string literals and the go out to the triplestore to query for the data.

If you are looking to use a triplestore it is important to distinguish between search and query.

Triplestore are really good for query but not so good for search. The basic problem with search is that is it mostly string based and this requires a regular expression query in SPARQL which is expensive from a hardware perspective. 

There are a few triple stores that use a hybrid model. In particular Jena Fuseki (http://jena.apache.org/documentation/query/text-query.html)

Thanks,

Jeff Mixter
Research Support Specialist
OCLC Research
614-761-5159
[log in to unmask]

________________________________________
From: Code for Libraries <[log in to unmask]> on behalf of Forrest, Stuart <[log in to unmask]>
Sent: Friday, December 19, 2014 10:00 AM
To: [log in to unmask]
Subject: Re: [CODE4LIB] rdf triplestores

Hi All

My question is what do you guys use triplestores for?

Thanks
Stuart


 ===============================================================================
Stuart Forrest PhD
Library Systems Specialist
Beaufort County Library
843 255 6450
[log in to unmask]

http://www.beaufortcountylibrary.org

For Leisure, For Learning, For Life



-----Original Message-----
From: Code for Libraries [mailto:[log in to unmask]] On Behalf Of Stefano Bargioni
Sent: Monday, November 11, 2013 8:53 AM
To: [log in to unmask]
Subject: Re: [CODE4LIB] rdf triplestores

My +1 for Joseki.
sb

On 11/nov/2013, at 06.12, Eric Lease Morgan wrote:

> What is your favorite RDF triplestore?
>
> I am able to convert numerous library-related metadata formats into RDF/XML. In a minimal way, I can then contribute to the Semantic Web by simply putting the resulting files on an HTTP file system. But if I were to import my RDF/XML into a triplestore, then I could do a lot more. Jena seems like a good option. So does Openlink Virtuoso.
>
> What experience do y'all have with these tools, and do you know how to import RDF/XML into them?
>
> --
> Eric Lease Morgan
>